A faunistic study of genus Chasmogenus Sharp, 1882 of China (Coleoptera, Hydrophilidae) Author Jia, Fenglong Author Tang, Yu-dan text ZooKeys 2018 738 59 66 http://dx.doi.org/10.3897/zookeys.738.21711 journal article http://dx.doi.org/10.3897/zookeys.738.21711 1313-2970-738-59 943CB4720D3A499A8D8C5970E042D227 Chasmogenus Sharp, 1882 Chasmogenus Sharp, 1882: 73. Type species: Chasmogenus fragilis Sharp. Crephelochares Kuwert, 1890: 38. Type species: Helochares livornicus Kuwert. Syn.: d'Orchymont 1919: 148; Fernandez 1986 : 148. Diagnosis. The following character combinations can be used to separate Chasmogenus Sharp, 1882 from other genera: 1) maxillary palpi at least as long as width of head; 2) second maxillary palpomeres curved inward, apical segment almost symmetrical, as long as penultimate; 3) clypeus not concealing labrum and not expanded in front of eyes; 4) mesoventrite with rather strong median carina for entire length; 5) elytra without striae or rows of serial punctures; 6) elytra with sutural stria on posterior half; 7) posterior margin of 5th abdominal ventrite with a small apical emargination.